Halo Structure and RR Lyrae Stars in the SDSS-II Supernova Survey

密歇根州立大学的Horace Smith博士将在斯隆数字巡天II超新星巡天期间反复覆盖的300平方度的天空中识别RR天琴座恒星。这些天琴座RR星的光曲线、金属丰度，以及在某些情况下的径向速度将被确定。这项调查不仅将揭示迄今为止尚未完全研究的天琴座RR星的整体空间分布，而且还可能确定与不同合并事件相关的天琴座RR星的子集。天琴座RR星是脉动恒星，其进化的祖先是光环形成的目击者，是极好的标准蜡烛，可以为银河系的形成提供特别的见解。这项拟议的研究将成为密歇根州立大学天体物理学研究生和本科生培训的重要组成部分。这项研究，连同密歇根州立大学正在进行的其他变星研究，也将为吸引密歇根地区的天文学家参加当地的变星会议提供一个焦点。通过网页介绍研究成果，以及在校园天文台开放日晚上向公众介绍研究成果，将产生更广泛的影响。在校园天文台举行的会议上，中学教师将被介绍到观察和这项研究，教师们将能够获得自己的观察结果

Dr. Horace Smith, at Michigan State University, will identify RR Lyrae stars within the 300 square degree strip of sky that is being repeatedly covered during the Sloan Digital Sky Survey II supernova survey. Light curves, metallicities, and, in some cases, radial velocities will be determined for these RR Lyrae stars. This survey will not only reveal the overall space distribution of RR Lyrae stars in a hitherto very incompletely studied region of the sky, but it is also likely to identify subsets of RR Lyrae stars associated with distinct merger events. RR Lyrae stars, pulsating stars whose evolutionary progenitors were eyewitnesses to the formation of the halo and which are excellent standard candles, can provide particular insight into the building of the Milky Way.The proposed research will form an important part of the training of both graduate and undergraduate astrophysics students at Michigan State University. This research, together with other variable star studies being carried out at MSU, will also provide a focus for drawing astronomers in the Michigan area to local meetings on variable stars. A wider impact will be achieved through a web page describing the research and also through presentations to the public during open house nights at the campus observatory. Secondary school teachers will be introduced to observing and to this research at sessions held at the campus observatory, where the teachers will be able to obtain observations of their own